Authoring Workflow¶

Demonator includes two features to streamline the process of writing and testing demo configs: dry-run mode and hot reload.

Dry-run mode¶

Preview the entire demo flow without typing animation or command execution:

demonator --dry-run
demonator --dry-run -c my-demo.yml

Dry-run output shows:

Each step with the configured prompt
Chapter boundaries (if using chapters)
Setup and teardown commands
Annotations for special features:
[no-exec] — step won't execute the command
[fake-output] — step has pre-defined output (shown indented with >)
[wait-for] — step waits for a pattern
[interactive] — step has expect/send interactions
[conditional] — step has if or unless conditions
[capture] — step captures output

Example dry-run output:

[setup]
  mkdir -p /tmp/demo
  echo 'ready'

── Setup ──
~ $ git clone git@github.com:example/myproject.git
~ $ cd myproject

── Build ──
This builds in release mode.
~ $ cargo build --release  [wait-for]
~ $ cargo test

── Deploy ──
~ $ kubectl apply -f deploy.yml  [conditional]

[teardown]
  rm -rf /tmp/demo

Hot reload¶

Watch the config file and automatically re-run the demo when it changes:

demonator --watch
demonator --watch -c my-demo.yml

The workflow:

The demo runs normally (you press Enter through steps)
After the last step, demonator prints "watching for changes..."
Edit and save your YAML file
The screen clears and the demo restarts automatically
Press Ctrl+C to exit

This gives you a tight feedback loop when authoring demos — make a change, see the result immediately.

Combining both¶

A good authoring workflow:

Start with --dry-run to sketch out the structure:
```
demonator --dry-run -c my-demo.yml
```
Switch to --watch to iterate on timing and output:
```
demonator --watch -c my-demo.yml
```
Do a final run without flags to rehearse the real presentation:
```
demonator -c my-demo.yml
```

Tips¶

Dry-run is instant — use it to quickly check that your YAML parses correctly and the step order makes sense
Hot reload polls the file every 500ms, so changes are picked up almost immediately
Hot reload clears the screen before each re-run, so you always see a fresh start
Setup commands still run in dry-run mode (so your environment is ready), but teardown does not